Change AtomicStack to use StackReference
Previously used Object*, using StackReference saves memory on 64 bit
devices.
Bug: 12935052
Bug: 17643507
Change-Id: I035878690054eeeb24d655a900b8f26c837703ff
diff --git a/runtime/gc/collector/mark_sweep.cc b/runtime/gc/collector/mark_sweep.cc
index 04fb694..1959c09 100644
--- a/runtime/gc/collector/mark_sweep.cc
+++ b/runtime/gc/collector/mark_sweep.cc
@@ -330,11 +330,11 @@
// Someone else acquired the lock and expanded the mark stack before us.
return;
}
- std::vector<Object*> temp(mark_stack_->Begin(), mark_stack_->End());
+ std::vector<StackReference<Object>> temp(mark_stack_->Begin(), mark_stack_->End());
CHECK_LE(mark_stack_->Size(), new_size);
mark_stack_->Resize(new_size);
- for (const auto& obj : temp) {
- mark_stack_->PushBack(obj);
+ for (auto& obj : temp) {
+ mark_stack_->PushBack(obj.AsMirrorPtr());
}
}
@@ -554,7 +554,7 @@
class MarkStackTask : public Task {
public:
MarkStackTask(ThreadPool* thread_pool, MarkSweep* mark_sweep, size_t mark_stack_size,
- Object** mark_stack)
+ StackReference<Object>* mark_stack)
: mark_sweep_(mark_sweep),
thread_pool_(thread_pool),
mark_stack_pos_(mark_stack_size) {
@@ -627,11 +627,11 @@
MarkSweep* const mark_sweep_;
ThreadPool* const thread_pool_;
// Thread local mark stack for this task.
- Object* mark_stack_[kMaxSize];
+ StackReference<Object> mark_stack_[kMaxSize];
// Mark stack position.
size_t mark_stack_pos_;
- void MarkStackPush(Object* obj) ALWAYS_INLINE {
+ ALWAYS_INLINE void MarkStackPush(Object* obj) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
if (UNLIKELY(mark_stack_pos_ == kMaxSize)) {
// Mark stack overflow, give 1/2 the stack to the thread pool as a new work task.
mark_stack_pos_ /= 2;
@@ -641,7 +641,7 @@
}
DCHECK(obj != nullptr);
DCHECK_LT(mark_stack_pos_, kMaxSize);
- mark_stack_[mark_stack_pos_++] = obj;
+ mark_stack_[mark_stack_pos_++].Assign(obj);
}
virtual void Finalize() {
@@ -660,7 +660,7 @@
Object* obj = nullptr;
if (kUseMarkStackPrefetch) {
while (mark_stack_pos_ != 0 && prefetch_fifo.size() < kFifoSize) {
- Object* mark_stack_obj = mark_stack_[--mark_stack_pos_];
+ Object* const mark_stack_obj = mark_stack_[--mark_stack_pos_].AsMirrorPtr();
DCHECK(mark_stack_obj != nullptr);
__builtin_prefetch(mark_stack_obj);
prefetch_fifo.push_back(mark_stack_obj);
@@ -674,7 +674,7 @@
if (UNLIKELY(mark_stack_pos_ == 0)) {
break;
}
- obj = mark_stack_[--mark_stack_pos_];
+ obj = mark_stack_[--mark_stack_pos_].AsMirrorPtr();
}
DCHECK(obj != nullptr);
visitor(obj);
@@ -687,7 +687,7 @@
CardScanTask(ThreadPool* thread_pool, MarkSweep* mark_sweep,
accounting::ContinuousSpaceBitmap* bitmap,
uint8_t* begin, uint8_t* end, uint8_t minimum_age, size_t mark_stack_size,
- Object** mark_stack_obj, bool clear_card)
+ StackReference<Object>* mark_stack_obj, bool clear_card)
: MarkStackTask<false>(thread_pool, mark_sweep, mark_stack_size, mark_stack_obj),
bitmap_(bitmap),
begin_(begin),
@@ -742,8 +742,8 @@
TimingLogger::ScopedTiming t(paused ? "(Paused)ScanGrayObjects" : __FUNCTION__,
GetTimings());
// Try to take some of the mark stack since we can pass this off to the worker tasks.
- Object** mark_stack_begin = mark_stack_->Begin();
- Object** mark_stack_end = mark_stack_->End();
+ StackReference<Object>* mark_stack_begin = mark_stack_->Begin();
+ StackReference<Object>* mark_stack_end = mark_stack_->End();
const size_t mark_stack_size = mark_stack_end - mark_stack_begin;
// Estimated number of work tasks we will create.
const size_t mark_stack_tasks = GetHeap()->GetContinuousSpaces().size() * thread_count;
@@ -954,9 +954,9 @@
void MarkSweep::VerifyIsLive(const Object* obj) {
if (!heap_->GetLiveBitmap()->Test(obj)) {
- accounting::ObjectStack* allocation_stack = heap_->allocation_stack_.get();
- CHECK(std::find(allocation_stack->Begin(), allocation_stack->End(), obj) !=
- allocation_stack->End()) << "Found dead object " << obj << "\n" << heap_->DumpSpaces();
+ // TODO: Consider live stack? Has this code bitrotted?
+ CHECK(!heap_->allocation_stack_->Contains(obj))
+ << "Found dead object " << obj << "\n" << heap_->DumpSpaces();
}
}
@@ -1025,7 +1025,7 @@
ObjectBytePair freed;
ObjectBytePair freed_los;
// How many objects are left in the array, modified after each space is swept.
- Object** objects = allocations->Begin();
+ StackReference<Object>* objects = allocations->Begin();
size_t count = allocations->Size();
// Change the order to ensure that the non-moving space last swept as an optimization.
std::vector<space::ContinuousSpace*> sweep_spaces;
@@ -1053,9 +1053,9 @@
if (swap_bitmaps) {
std::swap(live_bitmap, mark_bitmap);
}
- Object** out = objects;
+ StackReference<Object>* out = objects;
for (size_t i = 0; i < count; ++i) {
- Object* obj = objects[i];
+ Object* const obj = objects[i].AsMirrorPtr();
if (kUseThreadLocalAllocationStack && obj == nullptr) {
continue;
}
@@ -1072,7 +1072,7 @@
chunk_free_buffer[chunk_free_pos++] = obj;
}
} else {
- *(out++) = obj;
+ (out++)->Assign(obj);
}
}
if (chunk_free_pos > 0) {
@@ -1094,7 +1094,7 @@
std::swap(large_live_objects, large_mark_objects);
}
for (size_t i = 0; i < count; ++i) {
- Object* obj = objects[i];
+ Object* const obj = objects[i].AsMirrorPtr();
// Handle large objects.
if (kUseThreadLocalAllocationStack && obj == nullptr) {
continue;
@@ -1195,7 +1195,7 @@
static_cast<size_t>(MarkStackTask<false>::kMaxSize));
CHECK_GT(chunk_size, 0U);
// Split the current mark stack up into work tasks.
- for (mirror::Object **it = mark_stack_->Begin(), **end = mark_stack_->End(); it < end; ) {
+ for (auto* it = mark_stack_->Begin(), *end = mark_stack_->End(); it < end; ) {
const size_t delta = std::min(static_cast<size_t>(end - it), chunk_size);
thread_pool->AddTask(self, new MarkStackTask<false>(thread_pool, this, delta, it));
it += delta;